1. Field of the Invention
This invention relates to a connector assembly including a pair of connectors connected together through a through hole formed through a vehicle body panel (fixing portion) or the like, and the invention also relates to an improved method of mounting the connector assembly.
2. Related art
A connector assembly is used for connecting wire harnesses, used in an automobile, together through a through hole formed through a vehicle body panel, a door panel or the like, and from the viewpoint of safety, it is necessary that a pair of connectors (which form the connector assembly), secured respectively to ends of the wire harnesses, should be completely fitted together.
However, a fitting force, required for fitting the two connector together, increases with the increase of the number of wires (signal wires, power wires or the like) of the wire harnesses, so that the possibility of a half-fitted condition becomes larger. Particularly in the type of connector assembly requiring dustproof and waterproof effects, a seal member, made of an elastic material, is provided at a fitting portion, and a reaction force is produced as a result of compression of this seal member, and therefore an incompletely-fitted condition of the connector assembly is liable to occur, and besides the efficiency of the mounting operation is not good.
Therefore, in a connector assembly-mounting method, disclosed for example in Japanese Patent Unexamined Publication No. 9-17508, a strip-like fitting-detection pin is provisionally inserted into a detection insertion hole, formed in a side wall of a first housing, in such a manner that this detection pin passes generally through an axis of the first housing, and in this condition a second housing is inserted into a fitting hole in the first housing.
Then, the fitting-detection pin is completely inserted into the detection insertion hole in the first housing, and guide ribs, formed on opposed inner surfaces of a detection pin recess formed in the second housing, are engaged with a cam groove (having a slanting surface) formed in the fitting-detection pin. Then, the second housing is pushed into the fitting hole in the first housing through the engagement between the cam groove and the guide ribs.
As a result, even if the number of wires to be connected to the two housings increases, the housings can be fitted together satisfactorily with a low operating force, and a half-fitted condition is eliminated, and the wires can be positively connected together.
If the two housings are not completely fitted together, the fitting-detection pin can not be completely inserted into the detection insertion hole in the first housing, and can not be pushed thereinto, and therefore by observing the fitting-detection pin, a half-fitted condition can be detected quite easily.
In such a half-fitted condition, the rear end portion of the fitting-detection pin projects from the side wall of the first housing, and in this condition, even if trying to mount the first housing in a panel hole in a panel, the first housing can be fixed since the rear end portion of the fitting-detection pin interferes with the edge portion of the panel hole. Therefore, the connector assembly in a half-fitted condition is prevented from being fixed to the panel hole.
However, in the connector assembly-mounting method disclosed in Japanese Patent Unexamined Publication No. 9-17508, when the two housings are to be connected together through the panel hole in the panel, and are to be fixed to this panel hole, the second housing, connected to ends of the wires, is beforehand pulled out of the panel hole in the panel, and the fitting-detection pin is completely inserted into the detection insertion hole, and the first and second housings are fitted together, and thereafter the first and second housing thus fitted together are returned to the panel hole, and are fixed to the panel hole, which leads to a problem that the efficiency of the operation is not good.
Therefore, for example, in the case of effecting the above connector-fitting operation of the connector assembly simultaneously when mounting a door on a vehicle body, it is necessary to effect the passing operation for beforehand pulling the second housing out of the panel hole in the panel, which leads to a problem that the door assembling operation is complicated.
It is therefore an object of this invention to solve the above problems, and more specifically to provide a connector assembly and a connector assembly-mounting method, in which two connectors can be fitted together with a lower inserting force, and a half-fitted condition is prevented, and the mounting operation can be effected easily.
The above object of the present invention has been achieved by a connector assembly including:
a generally cylindrical lock frame for being fixed to a is through hole in a fixing portion;
a first cam groove extending spirally along an axis of the lock frame in continuous relation to one open end of the lock frame;
a second cam groove extending spirally in the same direction as a direction of helically-extending of the first cam groove in continuous relation to the other open end of the lock frame;
a first connector which is fitted in the one open end of the lock frame, and has a first engagement projection engaged in the first cam groove; and
a second connector which is fitted in the other open end of the lock frame, and has a second engagement projection engaged in the second cam groove; provided in that:
the first engagement projection is engaged in a provisionally-retaining position of the first cam groove, thereby provisionally retaining the first connector at the one open end of the lock frame;
the second connector is inserted into the other open end of the lock frame fixed to the through hole, with the second engagement projection engaged in the second cam groove, so that the second connector is held in a provisionally-fitted condition relative to the first connector disposed in the provisionally-retaining position; and
the first and second cam grooves are so formed that when the second connector, while rotated following the second cam groove, is inserted into the lock frame, a force, which displaces the first connector from the provisionally-retaining position to a completely-retaining position while rotating the first connector, following the first cam groove, and also completely fits the first connector relative to the second connector, is exerted through the first and second engagement projections.
The above object of the present invention has been achieved by a method of mounting a connector assembly including a generally cylindrical lock frame for being fixed to a through hole in a fixing portion;
a first cam groove extending spirally along an axis of the lock frame in continuous relation to one open end of the lock frame;
a second cam groove extending spirally in the same direction as a direction of helically-extending of the first cam groove in continuous relation to the other open end of the lock frame;
a first connector which is fitted in the one open end of the lock frame, and has a first engagement projection engaged in the first cam groove; and
a second connector which is fitted in the other open end of the lock frame, and has a second engagement projection engaged in the second cam groove; the method being provided by the steps of:
engaging the first engagement projection in a provisionally-retaining position of the first cam groove, thereby provisionally retaining the first connector at the one open end of the lock frame, and subsequently fixing the lock frame to the through hole;
inserting the second connector into the other open end of the lock frame, with the second engagement projection engaged in the second cam groove, so that the second connector is held in a provisionally-fitted condition relative to the first connector disposed in the provisionally-retaining position; and
inserting the second connector into the lock frame while rotating the second connector, following the second cam groove, thereby displacing the first connector from the provisionally-retaining position to a completely-retaining position while rotating the first connector, following the first cam groove, so that the first and second connectors are completely fitted together.
In the connector assembly of the above construction and the above mounting method, the first and second connectors are connected together through the through hole in the fixing portion. For fixing the connector assembly to the through hole, the first engagement projection of the first connector, connected to ends of wires, is first engaged in the provisionally-retaining position in the first cam groove in the lock frame, thereby provisionally retaining the first connector at the one open end of the lock frame, and then the lock frame is fixed to the through hole in the fixing portion.
Then, the second connector is inserted into the other open end of the lock frame, with the second engagement projection engaged in the second cam groove in the lock frame, so that the second connector is held in a provisionally-fitted condition relative to the first connector disposed in the provisionally-retaining position.
Then, the second connector is inserted into the lock frame while rotating the second connector, following the second cam groove extending along the axis of the lock frame, so that the first connector rotates together with the second connector to be displaced from the provisionally-retaining position to the completely-retaining position, following the first cam groove.
The first and second cam grooves are so formed that the force to completely fit the first and second connectors together is exerted through the first and second engagement projections at this time, and therefore the operator is required merely to insert the second connector into the lock frame, beforehand fixed to the through hole, while rotating the second connector, and by doing so, the first and second connectors can be fitted together.
The forces to fit the first and second connectors together act respectively on the first and second connectors through the first and second engagement projections engaged respectively in the first and second cam grooves extending spirally along the axis of the lock frame, and therefore an eccentric force hardly acts on the two connectors during the time when the two connectors are fitted together.
Therefore, the two connectors are hardly twisted, and can be fitted together satisfactorily with the low operating force, and the two connectors can be positively connected together.
In the connector assembly of the above construction and the mounting method of mounting this connector assembly, the mutually-fitted condition of the first and second connectors corresponds to the position of rotation of the second connector relative to the lock frame, and therefore in order to completely fit the two connectors together, the second connector must be rotated into a predetermined position relative to the lock frame.
Therefore, by observing the position of rotation of the second connector relative to the lock frame, a half-fitted condition of the first and second connectors can be quite easily detected.
Preferably, at least two pairs of the first and second cam grooves, as well as at least two pairs of the first and second engagement projections, are provided, and the first and second cam grooves, as well as the first and second engagement projections, are disposed at an equal interval around the axis of the connector assembly. With this construction, the two connectors are less liable to be twisted, and the two connectors can be fitted together satisfactorily with the lower operating force.
Preferably, the first and second cam grooves have such configurations that the first and second connectors, held in the completely-fitted condition, can be rotated a predetermined angle relative to the lock frame. With this construction, by rotating the second connector through more than the predetermined angle relative to the lock frame, the two connectors can be completely fitted together regardless of molding errors and dimensional tolerances of the constituent parts.
Preferably, the first cam groove has a retaining projection for retaining the first engagement projection in the provisionally-retaining position. With this construction, the first connector can be easily provisionally retained relative to the lock frame, and the two connectors can be connected together more easily.